You can plug the pattern output into a MixRGB node with other colors of your own. Then use these colors for the diffuse color (or glossy color, glossy roughness, ...) and the BW pattern for the bumping/displacement.

Thanks for taking the time to make this great tutorial. Your whole blog is pretty handy, as a matter of fact.

I'm able to get everything running, but I can't get the voronoi texture to smear like the one you're showing. Where exactly is this smearing taking place? I've checked and double checked and haven't been able to find where I'm making the mistake.

Thanks again for sharing your node setups and for any additional help you can provide.